std::literals::chrono_literals::operator""ms

 

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std::chrono::duration

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duration::duration duration::operator= duration::count duration::zero duration::min duration::max duration::operator+duration::operator-	duration::operator++duration::operator-- duration::operator+=duration::operator-=duration::operator*=duration::operator/=duration::operator%=
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common_type treat_as_floating_point	duration_values formatter<std::chrono::duration> (C++20)

 

Defined in header <chrono>
constexpr std::chrono::milliseconds operator ""ms( unsigned long long ms );	(1)	(since C++14)
constexpr std::chrono::duration</*unspecified*/, std::milli>                                     operator ""ms( long double ms );	(2)	(since C++14)

Forms a std::chrono::duration literal representing milliseconds.

1) integer literal, returns exactly std::chrono::milliseconds(ms)

2) floating-point literal, returns a floating-point duration equivalent to std::chrono::milliseconds

Parameters

ms

-

the number of milliseconds

Return value

The std::chrono::duration literal.

Possible implementation

constexpr std::chrono::milliseconds operator ""ms(unsigned long long ms) { return std::chrono::milliseconds(ms); } constexpr std::chrono::duration<long double, std::milli> operator ""ms(long double ms) { return std::chrono::duration<long double, std::milli>(ms); }

Notes

This operator is declared in the namespace std::literals::chrono_literals, where both literals and chrono_literals are inline namespaces. Access to this operator can be gained with:

• using namespace std::literals,
• using namespace std::chrono_literals, or
• using namespace std::literals::chrono_literals.

In addition, within the namespace std::chrono, the directive using namespace literals::chrono_literals; is provided by the standard library, so that if a programmer uses using namespace std::chrono; to gain access to the classes in the chrono library, the corresponding literal operators become visible as well.

Example

Run this code

#include <iostream>
#include <chrono>
 
int main()
{
    using namespace std::chrono_literals;
    auto d1 = 250ms;
    std::chrono::milliseconds d2 = 1s;
    std::cout << "250ms = " << d1.count() << " milliseconds\n"
              << "1s = " << d2.count() << " milliseconds\n";
}

Output:

250ms = 250 milliseconds
1s = 1000 milliseconds

See also

(constructor)

constructs new duration (public member function of std::chrono::duration<Rep,Period>)